A child’s play area inside the first detention center specifically for mothers recently arriving from Central America with children, in Karnes City, Texas.
Photograph: Reuters

Young migrant children held in one of the most controversial privatised detention centres in the US have been restricted from playing with crayons after staff members accused them of causing damage to property.

The move has been branded as unnecessarily punitive by lawyers working on behalf of 600 mothers and children detained at the Karnes detention centre in Texas.

A spokeswoman for the Refugee and Immigrant Center for Education and Legal Services (RAICES), which provides pro bono legal support to detainees at Karnes, said detention centre staff enforced the ban after accusing children of damaging a table as they drew inside the prison’s visitation centre last week. The damage is said to have occurred as some mothers were taking legal advice.

In email correspondence seen by the Guardian, Immigration and Customs Enforcement (ICE) staff state the punishment was “an action resulting from crayons which RAICES staff/volunteers have given children which has caused property damage to the contractor”.

The GEO group, the $2bn global security company that operates the centre, has made over $57m from it since November last year, according to local media reports.

A spokesman for GEO group said “crayons, toys and books etc” were provided to children in other sectors of the detention centre, and the restriction only affected children playing in the visitors area.

Barbara Hines an adjunct professor at the University of Texas and RAICES member said in a letter to ICE that the reaction was disproportionate.

“Treating a child’s color markings as ‘destruction of property’ is altogether inappropriate. And such markings are a cost that comes with the detention of children. It is extremely disturbing that ICE’s concern for GEO’s property takes precedence over the well being of the children and their mothers’ rights to legal advice,” she wrote.

In an emailed statement, one 23-year-old detained mother said banning her children from drawing with crayons was already having an adverse effect.

“They are too young to read and if they just play can get too rowdy. We don’t always want them with us because some of the things we share we don’t want them to hear,” the mother said.